Gas-operated automatic rifle having a plurality of barrels



S. K. JANSON May 10, 1960 GAS-OPERATED AUTOMATIC RIFLE HAVING A PLURALITY OF BARRELS Filed June 27.

INVENTOR Stefan Kennefh Jonson May 10, 1960 s. K. JANsoN 2,935,915

GAS-OPERATED AUTOMATIC RIFLE HAVING A PLURALITY OF' BARRELS Filed June 27, 1956 3 Sheets-Sheer. 2

FIG. 5

INVENTOR Stefan Kenneth Jonson May l0, 1960 s. K. JANsoN GAS-OPERATED AUTOMATIC RIFLE HAVING A PLURALITY 0F BARRELS Filed June 2T, 1956 3 Sheets-Sheet 3 INVENTOR Stefo nneth Jonson B fm", Lrnwatu ATTORNEYS amper GAS-OPERA'ED AUTOMATIC RIFLE HAVING A Y FLURALHTY F EARRELS Stefan Kenneth Janson, New Haven, Conn., assigner to Olin Mathiesnn Chemical Corporatien, New Haven, fConn., a corporation of Virginia Application .lune 27, 1956, Serial No. 594,319

2 Claims. (Cl. 89-193).

This invention relates to gas-operated repeating, semiautomatic and full automatic rifles (hereinafter for convvenience called automatic rifles), and has for its object the provision of an improved rie of this character which and make closing contact with either Valve seat or assume the neutral position between the seats.

I prefer to use a simple bayonet type plug valve having i v different size ports to regulate the volume of gas which can pass from the chamber through the passageway to the gas cylinder.

crate the breech block, or as a long-stroke piston to operate the breech block in direct connection. Onefof Y'the important features of the invention is the provision of means to direct gas in a controlled amount from either barrel alone or from both barrels simultaneously,

l' to-thecylinder of theV gas-operated piston. The invention comprises duct means connecting each barrel with a single chamber having a valve which can assume a neutral position when both barrels are fired simultaneously, or a closed position for one barrel when only the other barrel is red alone to prevent the escape ofV gas through the empty barrel, and a passageway for directing gas from the chamber to the cylinder ofthe piston, 'Ihe improved gas-operated mechanism of the invention has the important characteristic feature of supplying the same elfective volume of gas under the same'pressure to the cylinder of the gas-operated piston, whether but "one barrel be tired or both barrels be ired simultaneously, and of preventing the escape of gas through either barrel when only the other is fired.

The gas-operated mechanism includes Ya housing, aidvantageously as a unitary'member, having two spaced apart holes, one for each barrel, each barrel being'snugly butremovably mounted in thehousing, la gas chamber having a ball valve loosely movablethe're'in, a Yseparate gas duct connecting each barrel bore with the chamber,

Y a seating surface for each duct which Vcan be Aclosed by the ball, a cylinder inthe housing for the gas-operated piston and a passageway connecting the chamber-With the cylinder, and means for varying vthe volume of gas thatcan pass through said passageway. Whenrboth barrels are tired simultaneously, the ball assumes V"a neutral or intermediate position between thev seats, the gas being free to enter the chamberfrom each barreLrbutlwhen one barrel is fired, the ball is thrown by the pressure of the gas from that Ybarrel intopseating engagement with the seating surface of the VYother barrel to' clo'sethat duct. In a preferred embodiment of the invention, I provide a cylindrical chamber in the housing located between Vand transverseto the longitudinal axisY ofthe barrels, and

the .ball makes av close but sliding tA inside thehamber.V

The ducts Soi' the Ybarrels are preferably in line With the longitudinal'axis of the chamber and connect Ythe Vends: oflthef'chamber with the bores of the barrels. An annular valve seat is provided around the duct leading into These arid other novel features ofthe invention'will be better understood after considering the following dis; cussion taken in conjunction with the accompanying drawings, in which:

Fig. 1 is a perspective view of anr automatic vrille in one embodiment of the invention; Fig. 2 is a fragmentary enlargement of a part of ythe rifle of Fig. 1, with parts removed;

Fig. 3 is a perspective view of the gas-operated mechanism of the rie of Fig. 1, with parts removed; Y Fig. 4 is a partial sectional view at 4--4 of Fig. 5;

Fig. 5 is a sectional view at 5-5 of Fig. 4;

Fig. 6 is a fragmentary sectional view at 6-6 of Y Fig- 5; Y Y

Fig. 7 is a fragmentary sectional View at 7--7 of Fig. 5; I'

Fig. 8 is a Vfragmentary sectional viewgat 8 8 of Fig. 6; and r p .Y

Fig. 9 is an enlarged sectional view at 9-9 of Fig. 5.

Fig. 1 illustrates one type of double barrel` rifle including the improved gas-operated mechanism of my i'n\ vention, and it is Vtobe understood that other types of vdouble barrel weapons may be employed suchlas antiaircraft and tank guns ofvariousucaliber's.- The.rifle illustrated is a so-called.. shoulder riile'intended to be held by a soldier and comprisesias illustrated in Fig; l',

two barrels 1 and 2, a receiver 3 to which the barrels arev removably attached, a` slide or momentum member 4 p into position, andra stock10. The slide hasa projecting handle` 12-for .the manual operation of the breech block,

' The rifle may include within the receiver anysuitable selector v'for controlling the action to lire either barrel as a Ysingle shot or both barrels simultaneously either, in semi-'automatic Yor full automatic fire', Awhich selector means Vmay be operated 'by the projecting knob 13.

Just'forwardof the receiver a housing legis mounted over the barrels and this housing is surrounded with a sheet metal guard l5 Vwhich also serves as a forearm for the Vriile. The gas-operated Ymechanism partially v enclosed within the guard 15 isshown in its `mostcornplete forminwFig. 3. The housing 14 isprefera'oly a uni# 'Y tary. steel member having parallelcylindrical bores 16 and 17 into which thebarrels l andZ aref inserted with i V5 l' 4' a tight sliding t so Athat they may be, removedieadily fromhthe receiver to which theyrare -attached as b'yhalf.;

threads (not shown) or in any other suitable `quick` takedown means. A cross pinliiA holdsl` the housing in a fixed position withrespect tothe barrels. ,jV` ';v Y. l, y 'The Vbarrels have, small holes or gas ductsAZ .and 21 (Eig. 4) v extending at `rightrfangles -to the, longitudinal anis. ofthe barrels andeaehduct has an exterior lsurrounding annular valve seat. Zand 2.3, preferably segments of spheres 1for making seating contachwith aball valve.A Inline with 'the' transverse axisof the twofducts a cylindricalgas chamber Z4 is formedwithin'fthe'hous-` 'ing and a hard metal ball 25 is 'inserted within'this gas each2 barrel, and the ball can travel acrossthe chamber Y l chamber.Y v 'iIpheball rnakes close Contact withthe charn-V ber butfis free to be movedacrossthechamber andto make seatingl'contact with either of the valve'seats or23.-Y` i if 1 f Patented May-fill), Y

The upper portion of the housing includes a gas cylinder 26 in which is mounted a cylindrical sleeve 27 in which the gas-operated piston 28 having a working face 28a is reciprocally slidable. The chamber 24 is connected to the cylinder 26 by means of a passageway V29 which is circular in cross section where it enters the cylinder 26 but is enlarged in the direction of the chamber 24 into which it enters as an elongated oblong port 30. This port is of such a size and shape that regardless of the position of the ball within the chamber there can be suilicient gas from either barrel to pass through the passageway 29 to operate the piston 23. As best shown in Fig. 4 the ball 25 can make seating engagement with one of the seats 22 or 23 and when in this position there is sufficient opening in the port 30 to admit the required amount of gas from the opposite barrel. When the ball takes a position intermediate between the two barrels, as when both barrels are n red simultaneously, then gas can enter the port 30 from both barrels simultaneously.

The cylinder 26 continues through to the rearward end of the housing and a bayonet type plug valve or selector 32 is inserted into the cylinder. This plug valve has an interior end portion having a concave opening 33 into which a plurality of diagonally disposed orices 34 and 35 are arranged so that on proper manipulation of the valve 32 one of these oriiices may be positioned to make coincident engagement with the passageway 29 so that gas may pass progressively from the bores of the barrels through one of the ducts 20 and 21, or either of them, into the chamber 24, through the passageway 29 and into the gas cylinder 26.

The interior of the cylinder 26 has an annulargroove 36 and two diametrically opposite longitudinal slots 37 and 37 leading into the groove 36. The rearward end portion of the valve member 32 has diametrically opposite locking lugs 38 and 39 which are inserted through the slots 37 and 37' to assume their position in the annular groove 36. The rearward end of the housing surrounding the cylinder 26 has transverse slots 42 and 43 in which a projecting lug 44 of the locking pin 45 makes locking engagement when in either of its two positions. The pin 45 is mounted in a hole 46 in the valve member and is held in the locking position illustrated in Fig. 9 by the coil spring 47. The pin is held in the position shown by means of a spring washer 48 that engages the flared end 49 of the pin. By inserting a rigid member, such as the nose of a bullet into the recess 50 the pin 45 may be depressed to a point where Vthe lug 44 is out of engagement with the slot 43 and While in this position the valve member 32 may be rotated to position the desired orice, 34 or 35, in coincident engagement with the passageway 29. When thus positioned, pin 45 is released to assume its locking position with the lug 45 in the slot 43 as shown in Fig. 5.

The gas piston 28 may be constructed as a short-action impulse member for initiating the movement of a weighted slide to unlock the breech block, or it may be constructed as a long-stroke piston with means connecting it to any suitable lock operating mechanism for the breech block. In the rifle illustrated, the piston serves as an impulse member, the rod 52 thereof having an end which strikes the forward face of the slide 4 (Fig. 2) when the piston is driven rearwardly a short distance, for example, about 3A, by the gas admitted to the cylinder 26. The rod 52 is normally held in a forward position by the spring 53 which bears on the face of the receiver at one end and on the disc 54 on the other end.

The double barrel automatic rie illustrated in the drawings is operated as follows: l

With both magazines loaded with cartridges the slide 4 is pulled rearwardly by means. of the handle 12 to unlock and open the breech block. On its release the slide and breech block travel forward by means of the usual return spring and the breech block pushes a cartridge into the chamber of each barrel. At the end of the travel of the breech block it becomes locked in iiring position. When the trigger is pressed both barrels are fired simultaneously. lf the selector is set for full automatic operation the gun will continue to re rapidly until the magazines are emptied. I it is set for semi-automatic operation, the barrels are both tired each time the trigger is pressed.

After the bullets pass beyond the ducts 20 and 21 the high pressure gas yfrom the riie bores enters the chamber 24, passes through the passageway 29 into the cylinder 26 and drives the piston 28 rearwardly. Since the gas passes through both of the ducts 20 and 21 at the same time the ball valve 25 assumes a neutral or intermediate position in the chamber and the gas from both barrels passes through the passageway 29 into the cylinder. In the embodiment of the invention illustrated, the piston 2S is constructed as an impulse member. rThe piston and rod 52 are normally held in a forward position by the spring 53 so that there is substantially no free space between the rearward end of the rod 52 and the face of the slide 4. The gas drives the piston rearwardly very rapidly causing the rod 52 to push the slide 4 and this induces such momentum into the slide that it travels rearwardly and unlocks the breech block carrying it rearwardly to the end of its stroke. in this rearward position, cartridges are pushed upwardly from the magazines and lare carried forward into the barrel chambers by the return of the breech block to its locked position. This cyclic operation is repeated until the lire is either stopped by the operator Vof the riile or the magazine is emptied. In order to assure the required gas pressure in the cylinder for imparting the necessary energy to the piston due to variations in the barrel pressure as a result of adverse conditions e.g. sand, mud, or cold Weather, the valve 32 may be set to bring the desired orifice, either 34 or 35, into coincident engagement with the passageway 29. These changes may be efected by pressing the `locking pin 45 (as best shown in Fig. 9) upwardly with a cartridge until the lug 44 passes beyond the slot 43 in which position the valve member may be rotated to the required position. When the pressure is released on the pin 45 it springs back into the original locked position.

I claim:

1. A gas system for a gas operated firearm having a plurality of barrels which may be fired individually or simultaneously comprising a gas chamber, a gas duct individual to each barrel and each communicating with said chamber, a single piston having a working face and operable in response to gas pressure to move axially, a passageway communicating with the chamber and with the working face of the piston, valve means disposed within the chamber androper'able selectively to direct gas from said barrels to said face through said passageway and selector means disposed between the face of the piston and the passageway for varying the volume of gas directed to the piston face.

2. The system of claim 1 where the valve means comprises a ball movable from a rst position wherein at least two gas ducts communicate with the face of the piston to a second position wherein the duct individual to one barrel is closed, said ball being further movable to a third position wherein the duct communicating with another barrel is closed.

References Cited in the le of this patent UNITED STATES PATENTS 315,521 Lord et al Apr. 14, 1885 853,715 Mondragon May 14, 1907 2,137,612 Higson Nov; 22, 1938 2,509,734 Higson May 30, 1950 2,627,388 Johnson et al. Feb. 3, 1953 FOREIGN PATENTS 850,746 France Sept. 18, 1939 

